The present invention relates to a stopper apparatus for a slide rail provided between a body and a drawer or the like.
In general, a slide rail is provided with a first rail and a second rail as disclosed in Japanese Utility Model No. 2541480. Each first rail of a pair of the slide rails is fixed to left and right side portions of a housing portion of a body, respectively, such that the longitudinal direction thereof is in alignment with the back and forth direction. Meanwhile, each second rail of the pair of slide rails is fixed to left and right side portions of a drawer housed in the housing portion of the body, respectively. Moreover, each second rail is supported so as to be movable in the back and forth direction by the corresponding first rail. Consequently, the drawer is supported so as to be movable in the back and forth direction by the housing portion of the body through the pair of slide rails.
A stopper apparatus is provided between the first rail and the second rail of the slide rail. The stopper apparatus, for example, inhibits the second rail from moving forward further than a predetermined position with respect to the first rail, thereby inhibiting the drawer from falling out of the body. The stopper member is provided with a lock portion which is mounted on a face facing the second rail (i.e., an inner face) of the first rail, such that the lock portion projects toward the second rail, and a stopper member which is formed in a face facing the first rail (i.e., an inner face) of the second rail.
The stopper member is formed of an elastic metal plate material. It has an attachment portion fixed to the second rail, a sloping plate portion (plate portion) which is formed so as to be continuous with a front end portion of the attachment portion and which is inclined such that a front portion of the sloping plate portion is closer to the first rail than the rear portion thereof, and a guide portion which is formed so as to be continuous with a front end portion of the sloping plate portion such that a front portion of the guide portion is closer to the second rail than the rear portion thereof. A lock hole (lock recess portion) is formed in the front end portion of the sloping plate portion into which the lock portion is received so as to freely get in and come out of the lock hole. The guide portion contacts the lock portion when the second rail moves in the forward direction to a predetermined first position. Therefore, when the second rail moves further in the forward direction, the guide portion slides on the lock portion. Consequently, the sloping plate portion is elastically deformed so as to approach the second rail. Subsequently, when the second rail moves to a predetermined second position, the lock hole faces the lock portion. Then, the sloping plate portion is elastically deformed so as to return to the original position such that the front end portion of the sloping plate portion approaches the first rail, and the lock portion is received in the lock hole. When an attempt is made to move the second rail in the forward direction with the lock portion being received in the lock hole, a rear end face of the lock hole contacts the lock portion, whereby the second rail 2 is inhibited from moving in the forward direction.
In the conventional stopper apparatus as described above, in order to reliably inhibit the second rail from moving forward further than the predetermined second position, it is necessary that when the second rail moves to the second position, the lock portion be reliably received in the lock hole and that this state be reliably maintained. In order to achieve this, a modulus of elasticity of the stopper member, particularly a modulus of elasticity of the sloping plate portion needs to become larger. By doing so, elastic force becomes large when the sloping plate portion returns to the original state, whereby the lock portion is reliably received in the lock hole. However, if elastic return force of the sloping plate portion is made larger by increasing the modulus of elasticity thereof, large stress is generated in the sloping plate portion when the sloping plate portion is elastically deformed toward the second rail by the guide portion. Particularly, large stress is generated at an intersection portion of the sloping plate portion and the attachment portion. Therefore, the stopper member could be damaged at the intersection portion of the sloping plate portion and the attachment portion at an early time.
Note that when the modulus of elasticity of the sloping plate portion is made smaller, stress generated in the sloping plate portion becomes also small, thereby preventing the stopper member from being damaged at an early time. In this case, however, since the sloping plate portion is elastically deformed even by small force, the lock portion may easily get out of the lock hole when force in the forward direction acts on the second rail. This makes it difficult to reliably inhibit the second rail from moving forward further than the predetermined second position.